Systematic orientation of fresh rectal suction biopsies improves histopathological diagnostics in hirschsprung’s disease – a method description and preliminary report

Background: Optimizing rectal suction biopsy (RSB) diagnostics in Hirschsprung’s disease (HD) may shorten diagnostic time and prevent need for repeated biopsies. Aim: To explore whether systematic orientation of fresh RSB specimens increased biopsy quality, diagnostic times, diagnostic efficacy, and histopathologic workload, and to explore these outcome measures for aganglionic specimens. Materials/Methods: This was an observational case-control study conducted at a national referral center for HD on data collected from the local HD-diagnostic register. From 2019 each fresh RSB was oriented by the collector in a notch in a foam cushion, placed in a separate cassette, and sent in formalin for pathological analysis. Outcome measures of oriented RSB samples collected 2019–2021 were compared to those of non-oriented RSB samples collected 2015–2018. Staining/immunohistochemistry consisted of hematoxylin eosin, S-100 and calretinin. Results: 78 children with 81 RSBs and 242 biopsy analyzes were included. The frequency of high-quality RSB specimens was higher in oriented: 40% (42/106) versus non-oriented 25% (34/136) (p = 0.018), the diagnostic turnaround time was shorter: 2 days (1–5) versus 3 days (2–8) (p = 0.015), and the number of additional sectioning/leveling/re-orientation per biopsy was lower: 7 (3–26) versus 16 (7–72) (p = 0.011). Specifically for aganglionic specimens, the frequency of high-quality biopsies was generally higher in oriented than in non-oriented RSB specimens: 47% (28/59) versus 14% (7/50) (p < 0.001); the diagnostic efficacy was higher 95% (19/20) versus 60% (9/15) (p = 0.027) and the diagnostic turnaround time shorter: 2 days (2–3) versus 3 days (2–8) (p = 0.036). Conclusions: Systematic orientation of fresh RSB specimens improves HD diagnostics. Improvement was consistent in aganglionic specimens.